北京科技大学学报Issue(8)：1025-1031,7.DOI:10.13374/j.issn1001-053x.2014.08.006
Ti--IF钢凝固过程中TiN的析出机理和规律
Precipitation mechanism and behavior of TiN during Ti-IF steel solidification
王金永 1刘建华 1刘建飞 1冯美兰 1周明伟 2廖志 2贾友生2
作者信息
- 1. 北京科技大学冶金工程研究院，北京100083
- 2. 涟源钢铁集团有限公司，涟源417009
- 折叠
摘要
Abstract
Characterization of TiN precipitation during Ti-IF steel solidification was analyzed by thermodynamics and the solidifica-tion segregation model. It is found that TiN inclusions cannot precipitate in liquid steel before solidification. In the earlier stage of so-lidification, TiN precipitates at low temperature in solidified steel. When the solid fraction reaches to 0.64, TiN can precipitate in solid steel around the solidification front at higher temperatures, due to the increased enrichment of Ti and N. However, at the end stage of solidification, TiN can not only precipitate in solidified steel, but also in molten steel, for the segregation of Ti and N is getting seri-ous. TiN distribution in the Ti-IF slab was observed by scanning electron microscopy ( SEM) . The results show that the number and size of TiN precipitates vary a lot from the slab surface to the center. The TiN size is increasing from the slab surface to the center, from 1-2μm to 5μm, and it is maximum in the area of 70 to 80 mm from the slab surface. In the middle of the slab in thickness, the TiN size is large, with an average size of 5μm;while in the center of the slab, the TiN size is getting smaller again, with an average size of 3μm. The TiN denseness is high in the surface layer of the slab, but decreases significantly in the center and middle. The pre-cipitation moment, the size and number of TiN precipitates are closely related with the segregation of Ti and N and the solidification rate.关键词
IF钢/氮化钛/凝固/偏析/析出Key words
IF steel/titanium nitride/solidification/segregation/precipitation分类
矿业与冶金引用本文复制引用
王金永,刘建华,刘建飞,冯美兰,周明伟,廖志,贾友生..Ti--IF钢凝固过程中TiN的析出机理和规律[J].北京科技大学学报,2014,(8):1025-1031,7.
